Elizabeth Moss has a lot of opinions about her co-stars and you better believe she voiced some of them during this week’s episode of Watch What Happens. To be fair though, the whole conversation came about to it when Andy Cohen asked her to comment on the rumors about her Mad Men co-star Jon Hamm’s… endowments, according to E!News. "Is it true what they say about Jon Hamm's ham?" Cohen asked. To her credit though, Moss tried to steer clear of the whole “issue” and replied with a rather demure comment.

"Well, I mean, we've all seen the pictures so I mean I would suppose so," Moss said. "That's all I know." She wasn’t so coy when talking about another colleague though. When asked about collaborating with Jeremy Piven, Moss didn’t hesitate to voice her opinion – which, as you may have guessed, wasn’t at all positive.

"That's a very good one. I could go on and on," Moss smiled, adding that Piven's dropping-out was him "being highly unprofessional."

This came after she was asked about the situation, when in 2008, she and Piven co-starred in the Broadway production Speed the Plow. Back then, Piven pulled out of the premiere last minute citing mercury poisoning, but Moss was quick to call a bluff. Moss revealed that she saw him a month after the theater shakeup at the Golden Globes, "when he was supposed to be really sick."